The present invention relates generally to roof-covering membranes, and more particularly, to an adjustable corner fitment and roof membrane system. Polymer-coated membranes may be used to cover substantially flat roofs. The membrane is preferably custom designed for the particular roof on which it is to be used. The roof measurements may be provided to a factory which may create a unitary membrane from separate pieces which have been heat welded together.
Items such as vents, ductwork, air conditioning units, and the like commonly protrude from the surface of a roof. The size and location of these items is preferably provided to the factory which creates the membrane. With this information, the factory may make provisions for these items in the membrane.
Providing a water-tight seal around a protrusion in a roof presents a number of problems. U.S. Pat. No. 4,799,086 and U.S. Pat. No. 4,872,296 disclose a method and a fitment which have been used to cover the corners of protrusions. The fitment of these patents comprises a first generally rectangular member segment, a side being part-way split interjacent its ends, and a second member segment with a triangularly-shaped corner portion conformed to loop shape and having its marginal edges overlying portions of the first segment contiguous to the split and being welded thereto in a continuous weld seam. This method and fitment work best when the angle of the corner is a right angle and the angle between the roof and the protrusion is a right angle.
In many cases, however, the corner is not a right angle, the protrusion is not at a right angle to the roof, or there is some other irregularity in the protrusion, such as the bottom and the top being different sizes. In these situations, known fitments and methods do not provide satisfactory results. The membrane must be folded or "bunched" in order to conform the membrane to the underlying structure. The folding and bunching is unsightly, and water may collect in the folds which may have deleterious effects on the roofing membrane and/or may lead to localized leaks at seams and at other places in the membrane. In addition, folding can lead to cracking of the roof membrane over time due in part to stress induced by the fold lines. Therefore, a need exists for an adjustable fitment and roof membrane system that provides a smooth transition no matter what the shape or angle of the underlying protrusion and that eliminates the need to fold or bunch the fitment or the roof membrane.
U.S. Pat. No. 5,706,610 provides one embodiment of an adjustable roof membrane which includes a universal fitment and a universal boot. The disclosure of U.S. Pat. No. 5,706,610 is hereby incorporated by reference. In this embodiment, the universal fitment has a body with preferably three sides, a tab, and a neck connecting a corner of the body to the tab. The body is preferably either substantially square or substantially triangular. The patent also discloses an embodiment of a universal boot. The universal boot has a generally rectangular section with a split extending vertically in a side, and it has a fitment with a body having at least three sides, a tab, and a neck connecting a corner of the body to the tab. The tab of the fitment is preferably welded to the back of the rectangular section above the split.
The present invention provides another embodiment of an adjustable fitment and roof membrane system and a method for making the adjustable fitment and roof membrane system. The fitment may be useful with roof membranes to cover exposed roof areas around a vertical protrusion in a roof. As used herein, a vertical protrusion includes all protrusions that have a vertical component. The fitment may be partially secured to a roof membrane, a boot, and/or a spanning strip prior to being positioned at the corner of a vertical protrusion. Alternatively, the fitment may be positioned independently of the other components at the corner of a vertical protrusion. After the fitment is positioned at the corner of a vertical protrusion, a floating portion of the fitment may be adjusted to fit the corner of the vertical protrusion so that there is minimal or no folding or bunching of the material of the fitment. In this adjusted position, the floating portion of the fitment may be heat welded or otherwise secured to another portion of the fitment, and the fitment may be finally heat welded or otherwise secured to the roof membrane, the boot, and/or the spanning strips.
In addition to the novel features and advantages mentioned above, other objects and advantages of the present invention will be readily apparent from the following descriptions of the drawings and preferred embodiments.